Suspected drug hitmen kidnapped a Mexican journalist after he left work, shot him and left a threatening message on his body in an upsurge of attacks on the media, his newspaper said yesterday.

Gunmen forced Valentin Valdes out of his car as he left the daily Zocalo in the industrial city of Saltillo in Coahuila state near the US border on Thursday night.

Hours later, police found his body dumped outside a motel in Saltillo, where an American anti-kidnapping expert was abducted in December 2008.

Officials at the Coahuila state attorney general's office said Mr Valdes, who wrote about local city issues, was likely targeted by drug gangs.

Gunmen left a scrawled message on Mr Valdes' chest, Zocalo said on its website. Authorities declined to give more details but Mexican media said it was a threat against Coahuila state prosecutor Jesus Torres, who launched an anti-crime crackdown in December.

Suspected hitmen killed another journalist in the Mexican resort town of Tulum just before Christmas and abducted a journalist in Sinaloa state, home to the country's most powerful cartel, on December 30.

Saltillo and the nearby cities of Monterrey, Reynosa and Matamoros are controlled by the Gulf cartel and its armed wing, the Zetas, which run drugs through the area into Texas and use the manufacturing cities to launder drug profits.

Across Mexico, a fight between rival cartels for control of the multibillion dollar drug trade in Mexico and the US has killed 17,000 people since President Felipe Calderon launched his anti-drug campaign at the end of 2006.

Investors and officials in Washington are increasingly concerned that the escalating violence is overwhelming Mexico's 49,000 troops sent by Mr Calderon to fight the cartels.